The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent the work is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Various countries or regions differ in standards in the distribution of mains electricity. The mains voltage signal is an example of mains electricity that is distributed and that is used to power various devices such as lighting, portable appliances, home networking nodes (e.g., multimedia home networking nodes), other networked nodes, and/or other systems and/or devices that require power. A mains voltage signal is also commonly referred to as a line voltage or as a domestic mains signal. As an example, the mains voltage is approximately 120 Vrms (at a frequency of approximately 60 Hz) in the United States, and approximately 230 Vrms (at a frequency of approximately 50 Hz) in Spain. Other countries and/or regions vary in their rules on the distribution of the mains voltage.
For safety reasons, the mains voltage circuitry for delivering the mains voltage signal is electrically isolated from low voltage circuitries for powering various devices such as, for example, appliances, home networking nodes, and/or other networked nodes. Additionally, a zero crossing detector is typically used to provide synchronization with the mains voltage cycle of the mains voltage signal. This synchronization of the mains voltage cycle allows for synchronized communications among and/or between the low voltage circuitries in the nodes in a network.
A zero crossing detector will detect the zero crossing point of the mains voltage signal, and this zero crossing point indicates a space location (with respect to time) of the mains voltage signal. The detection of the zero crossing point of the mains voltage signal is used for synchronizing the mains voltage cycle.